Economically viable electromechanical tensile testing equipment for stretchable sensor assessment.

The growing interest in soft robotics increases the demand for stretchable sensors. The high performance of stretchable sensors depends much on the linearity, reliability and hysteresis of the stretchable conductive materials. In the applications of conductive materials such as in dielectric elastomer actuators, a stretchable conductive material should maintain the conductivity while sustaining large and multiple cycles of stretch and release tests. To understand the stretchable electrode quality, researchers should perform an electromechanical test. However, researchers require a high investment cost to use a professional type of electromechanical tensile test. In this research, we proposed an economically viable version of the Do-it-yourself (DIY) electromechanical tensile test (EMTT) to resolve the high investment cost problems. The DIY-EMTT is based on the Arduino-nano module. We integrate the load cell, displacement sensor, motor linear stage and DIY resistance meter. We can use the DIY mechanism to suppress the instrumental cost from thousands to hundreds of dollars. Furthermore, we provide a step-by-step guide to build the DIY-EMTT. We expect our DIY-EMTT to boost stretchable sensor development in soft robotics.

Protocol for manufacturing the GFRP sample using VARI applied to a modified complex Arcan fixture.

Manufacturing techniques play an essential role in obtaining optimum mechanical properties of composites. Vacuum-assisted resin infusion (VARI) is a composite fabrication approach for optimal fiber volume fraction. Here, we present a protocol for manufacturing glass fiber-reinforced polymer (GFRP) samples by applying VARI to a modified complex Arcan fixture. We describe steps for material preparation, molding preparation, setting vacuum system, resin mixing, and degassing. We then detail procedures for vacuum infusion process and cutting composites for shear testing samples. For complete details on the use and execution of this protocol, please refer to Alandro et al.1.

Surface roughness and dimension accuracy data from hybrid manufacturing process using PLA material.

This paper introduces a comprehensive dataset focusing on the surface roughness and dimensional accuracy of 3D printed specimens derived from a hybrid manufacturing process. The design of these specimens incorporates surfaces oriented at 0˚, 45˚, and 90˚ angles for surface roughness testing, along with cylindrical, radial, and pocket areas to evaluate dimensional accuracy. Utilizing PLA material, the specimens undergo a printing phase followed by milling within the same machine, thereby enhancing both surface roughness and dimensional quality. Surface roughness data is gathered through a surface roughness tester, while dimensional accuracy is assessed using a digital vernier caliper. The dataset includes comparative analyses conducted before and after the hybrid manufacturing process, revealing notable improvements in both surface roughness and dimensional accuracy post-processing. These findings furnish valuable insights for researchers and engineers engaged in hybrid manufacturing processes involving PLA material, serving as a foundational resource for further investigations and advancements in the field.

Investigating the Characteristics of Nano-Graphite Composites Additively Manufactured Using Stereolithography.

Stereolithography has emerged as a recent method in fabricating complex structures with high accuracy. Components using resin have poorer properties. The current study investigates the improvement in the properties of nano-graphite composites fabricated by the SLA technique. The properties are compared for plain resin and 0.2%, 0.5%, 1%, 3%, and 5% (w/v) of nano-graphite mixed with the UV-curable resin. Various analyses were conducted, including viscosity, UV spectroscopy, moisture content, water absorption, gel content, tensile, bending, hardness testing, and microscopic characterization. The results from the experiments showed a difference in the results of each percentage of the specimen tested, such as the specimen property, which shows that the greater the percentage of nano-graphite added (5%), the opaquer the specimen will appear and less light will be reflected. Viscosity testing shows that the greater the percentage of nano-graphite added to the resin, the greater the viscosity. UV spectroscopy testing produced information about the electronic structure and the structure of molecules, such as their composition, purity, and concentration. Observations from the moisture content analysis found that the moisture content in specimens with higher percentages of nano-graphite affected physical and mechanical properties, leading to easier warping, cracking, decreased strength, etc. Tensile and bending testing shows that the greater the percentage of nano-graphite added, the greater the effect on physical and mechanical properties, including fracture. However, certain tests did not consistently yield significant variations among specimens when different percentages of nano-graphite were added, as particularly evident in chemical resistance testing. This study offers valuable insights into the application of nano-graphite composites fabricated via the SLA method.

Load-displacement experimental data from shear loading of hybrid GFRP-graphite filler using a complex Arcan fixture.

This paper presents a dataset of load-displacement obtained from shear loading tests on pure GFRP laminates and hybrid GFRP-graphite filler laminates. The specimens were cut according to the ASTM D 7078 standard, and the width and thickness of the notch area were measured at least three times. Shear loading was applied at a rate of 2 mm/min, and data were recorded from unloading until specimen failure. The data provides information on the maximum load and unique behavior of GFRP laminates. Based on the obtained load, the shear stress (MPa) unit can be calculated. This data can serve as a basis for researchers and engineers working with GFRP laminates and hybrid GFRP-graphite filler laminates.

Effects of biodegradable- and non-biodegradable-rich waste separation on ash deposition behaviour during coal and refuse-derived fuel co-combustion.

The potential impact of ash deposition during the combustion of separated biodegradable- and non-biodegradable-rich waste of refuse-derived fuel (RDF) was evaluated in this study. Theoretical prediction, drop tube furnace experimental combustion, and ash observation were performed to comprehensively investigate their ash deposit behaviour. The results show that high CaO and Cl in RDFs result in severe sintering and rust in the metal surface. The high ash deposit weight and aggregated sticky particles are observed during single-firing RDFs. Furthermore, adding 5 wt% of biodegradable-rich RDF or mixed RDF to coal has a less significant effect on ash deposition. However, several aggregate particles and metal degradation are observed during the combustion of mixed coal with the addition of 5 wt% non-biodegradable-rich RDF. The high Cl in non-biodegradable-rich RDF affects the ash deposition behaviour significantly. This research provides valuable insights into optimising coal-RDF co-combustion, especially with separating biodegradable- and non-biodegradable-rich RDFs.

Characterization of sago tree parts from Sentani, Papua, Indonesia for biomass energy utilization.

Biomass derived from organic waste in industrial processes is an effective method to mitigate the negative impacts of agricultural waste materials. In Sentani, Papua, one such potential biomass source is sago tree waste. This study characterized the waste from the bark, middle, and inner parts of the sago tree to evaluate its biomass energy potential. Scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis of the complete sample revealed that oxygen, carbon, and silicon were the primary elements, with carbon content ranging from 30.75 % to 38.87 %. This indicates that all parts of the sago plant have the potential to be used as biomass fuel. Thermogravimetric analysis (TGA) results showed that the inner section of the sago had the lowest moisture content at approximately 13.3 %, followed by the outer part at 42 % and the bark at 55 %. The inner section had the highest lignin content, approximately 37 %, and exhibited the slowest thermal degradation in the differential thermal analysis (DTA) profile. The outer and bark parts of the sago were more reactive in stage II of the DTA profile, suggesting a higher concentration of cellulose and hemicellulose compared to lignin, making them suitable for gasification and pyrolysis. The heating value of sago bark was determined to be 12.85 MJ/kg (adb). These findings underscore the potential of sago waste as a renewable energy source, particularly in remote areas.

Excellent Characteristics of Environmentally Friendly 3D-Printed Nasopharyngeal Swabs for Medical Sample Collection.

3D-printed nasopharyngeal swabs for medical sample collection have been manufactured via additive manufacturing (AM), evaluated, and characterized in the present study. A multi-part component of nasopharyngeal swabs was proposed, in which the swab and handle were manufactured separately to reach sustainable production and environmentally friendly products. The swab was investigated using tensile, flexural, surface roughness, dimensional accuracy, and sample collection testing. The influence of printing parameters and post-curing time treatment on the mechanical properties, surface roughness, and dimensional accuracy of 3D-printed nasopharyngeal swabs were also evaluated. The result showed that 3D-printed nasopharyngeal swab shows outstanding tensile strength compared to the commercial flock nasopharyngeal swab. Moreover, the swab neck flexibility test showed that both PLA and dental non-castable 3D-printed nasopharyngeal swabs were able to bend 180°. Subsequently, the surface roughness of 3D-printed nasopharyngeal swab was identic with the commercial flock nasopharyngeal swab. The proposed 3D-printed nasopharyngeal swab design could carry an artificial mucus sample of 141.6 mg at a viscosity of 9455.4 mPa.s. The cost to fabricate a 3D-printed nasopharyngeal swab was estimated at USD0.01-0.02 per swab. 3D-printed nasopharyngeal swab shows potential as a feasible option, greener, less medical waste, and more sustainable.

The Interconnection of Carbon Active Addition on Mechanical Properties of Hybrid Agel/Glass Fiber-Reinforced Green Composite.

Nowadays, the hybridization of natural and glass fiber has promised several advantages as a green composite. Nevertheless, their different characteristics lead to poor mechanical bonding. In this work, agel fiber and glass fiber was used as reinforcements, and activated carbon filler was added to the polymer matrix of a hybrid composite to modify its characteristics and mechanical properties. A tensile and bending test was conducted to evaluate the effect of three different weight percentages of activated carbon filler (1, 2, and 4 wt%). Vacuum-assisted resin infusion was used to manufacture the hybrid composite to obtain the high-quality composite. The results have revealed that adding 1 wt% filler yielded the most optimum result with the highest tensile strength, flexural strength, and elastic modulus, respectively: 112.90 MPa, 85.26 MPa, and 1.80 GPa. A higher weight percentage of activated carbon filler on the composite reduced its mechanical properties. The lowest test value was shown by the composite with 4 wt%. The micrograph observations have proven that the 4 wt% composite formed agglomeration filler that can induce stress concentration and reduce its mechanical performance. Adding 1 wt% filler offered the best dispersion in the matrix, which can enhance better load transfer capability.

Excellent performance of hybrid model manufactured via additive manufacturing process reinforced with GFRP for sport climbing equipment.

The figure eight model was successfully manufactured, analyzed, and characterized in the present study. The model was manufactured via 3D printing fused deposition modelling (FDM) and then reinforced with glass fiber-reinforced polymers (GFRP). There are three different designs in figure eight that are examined, and each design is made using 3D printing FDM and coated with GFRP, a hybrid material, as shown. Specimens that have been made from each design are then evaluated by tensile test, hardness test, surface roughness test, and density test. The results showed that the hybrid figure eight lamination with polylactic acid (PLA) and GFRP material could increase the tensile strength by more than two times higher. The highest tensile strength lies in design 1 with 4977, 3 N. Moreover, the highest hardness value occurred for design two at 75.1 Shore D, and the highest average density lies in design three at 1.2 g/mm3. The study also showed that the lowest cost occurred in hybrid design three at $ 1.2 per item. Based on the present study, the GFRP reinforcement can extend the model's performance with affordable cost and retain figure eight from the failure.

Experimental Investigation of Effect of L-Profile Hybrid Aluminium/GFRP to the Axial and Lateral Characteristic.

The current study investigates the effect of a hybrid L-profile aluminium/glass-fiber-reinforced polymer stacking sequence under axial and lateral compression loads. Four stacking sequences are studied: aluminium (A)-glass-fiber (GF)-AGF, GFA, GFAGF, and AGFA. In the axial compression test, the aluminium/GFRP hybrid tends to crush in a more progressive and stable failure than the net aluminium and net GFRP specimens, with a relatively more stable load-carrying capacity throughout the experimental tests. The AGF stacking sequence was second, with an energy absorption of 145.31 kJ, following AGFA at 157.19 kJ. The load-carrying capacity of AGFA was the highest, with an average peak crushing force of 24.59 kN. The second-highest peak crushing force, 14.94 kN, was achieved by GFAGF. The highest amount of energy absorption, 157.19 J, was achieved by the AGFA specimen. The lateral compression test showed a significant increase in load-carrying and energy absorption capacity in the aluminium/GFRP hybrid specimens compared to the net GFRP specimens. AGF had the highest energy absorption with 10.41 J, followed by AGFA with 9.49 J. AGF also had the highest peak crushing force with 2.98 kN, followed by AGFA with 2.16 kN. The most crashworthy stacking sequence among the four variations tested in this experimental research was the AGF stacking sequence because of its great load-carrying capacity, energy absorption, and specific energy absorption in axial and lateral loading. The study provides greater insight into the failure of hybrid composite laminates under lateral and axial compression.

Broad-class volatile organic compounds (VOCs) detection via polyaniline/zinc oxide (PANI/ZnO) composite materials as gas sensor application.

Metal-oxide doped conductive polymers have been investigated as sensors in the field of gas-sensing. Recent developments have highlighted the role of intrinsically conductive polymers, that have reportedly offered high surface response towards the detection of volatile organic compounds (VOCs). In this work, we optimize the development of gas-sensors made of Polyaniline/Zinc oxide (PANI/ZnO) composite, capable of detecting a varied class of VOCs such as, ammonia, acetone, formaldehyde, methanol, and ethanol. The conductivity of these sensors is evaluated at room temperature and are investigated until saturation. In addition to the final application, this work also focusses on the synthesis strategies to achieve an 'optimal' matrix-to-additive ratio, such that superior chemical response is paralleled with mechanical robustness for PANI based sensors. The PANI/ZnO composites are casted into sensors bearing different additive ratios, via a drop-casting method and the same is evaluated for its formability and mechanical behavior. Physio-chemical characterization was performed using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), and Energy Dispersive X-ray Analysis (EDX) and we report on an exceptional selectivity for ammonia with an average sensor response of 3496.67 mV by all the sensors, when fabricated using different matrix-additive ratios. This result is superior to what is observed for Pure- PANI sensors that were selective only to methanol and ethanol. The addition of ZnO in the smallest fraction, already offers a broader range of selectivity, e.g., PANI/ZnO 90:10 sensor was selective to formaldehyde as assessed using pattern recognition.

Recent Progress on Natural Fibers Mixed with CFRP and GFRP: Properties, Characteristics, and Failure Behaviour.

Research on natural-fiber-reinforced polymer composite is continuously developing. Natural fibers from flora have received considerable attention from researchers because their use in biobased composites is safe and sustainable for the environment. Natural fibers that mixed with Carbon Fiber and or Glass Fiber are low-cost, lightweight, and biodegradable and have lower environmental influences than metal-based materials. This study highlights and comprehensively reviews the natural fibers utilized as reinforcements in polyester composites, including jute, bamboo, sisal, kenaf, flax, and banana. The properties of composite materials consisting of natural and synthetic fibers, such as tensile strength, flexural strength, fatigue, and hardness, are investigated in this study. This paper aims to summarize, classify, and collect studies related to the latest composite hybrid science consisting of natural and synthetic fibers and their applications. Furthermore, this paper includes but is not limited to preparation, mechanism, characterization, and evaluation of hybrid composite laminates in different methods and modes. In general, natural fiber composites produce a larger volume of composite, but their strength is weaker than GFRP/CFRP even with the same number of layers. The use of synthetic fibers combined with natural fibers can provide better strength of hybrid composite.

Failure Prediction and Surface Characterization of GFRP Laminates: A Study of Stepwise Loading.

The present study explores the failure and surface characteristics of Glass Fiber-Reinforced Polymers (GFRP). Stepwise loading was applied in this study to understand the multi-static loading effect on the laminates before final failure. The loading was set three times to reach 10 kN with loading-unloading movement before final load until failure. The results showed that the angle of the GFRP UD laminates' position significantly impacts the system's failure. The results were analyzed using theoretical calculation experiment analysis, and then the failure sample was identified using ASTM D3039 standard failure. The laminates with 0° layer on edge ([0/90]S laminates) underwent preliminary failure before final failure. The mechanism of stepwise loading can be used to detect the effect of preliminary failure on the laminates. The [0/90]S laminates are subjected to stress concentration on the edge due to fiber alignment and discontinued fibers in the 0-degree direction. This fiber then fails due to debonding between the fiber and the matrix. The laminates' strength showed that [90/0]S specimens have an average higher strength with 334.45 MPa than the [0/90]S laminates with 227.8 MPa. For surface roughness, the value of Ra increases more than six times in the 0° direction and three times in the 90° direction. Moreover, shore D hardness showed that the hardness was decreased from 85.6 SD then decreased to 70.4 SD for [0/90]S and 65.9 SD for [90/0]S. The matrix debonding, layer delamination and fiber breakage were reported as the failure mode behavior of the laminates.

The hypodermic syringe performance based on the ISO 7886-1:2017: A narrative review.

A syringe is used to inject fluid or medicine into the patient's soft tissue. The main components of the syringe were the needle, barrel, and plunger. The use of syringes in the medical world is relatively high, and especially since the COVID-19 pandemic, the use of hypodermic syringes increased sharply due to vaccination. The syringe used must be effective and of good quality, so the International Organization for Standardization (ISO) has published test procedures and minimum specifications for hypodermic syringes. The performance of the syringe can be observed from the dead space, force piston operation, water and air leakage, and fitting position of the plunger in the barrel. This review shows that most researchers use the weighing method to measure the dead space, although some use other methods. The researchers found that most of the products met the minimum specifications of the ISO, and that the dimensions and shape of the syringe affected the dead space. Researchers have not examined other performance measures recommended by the ISO. Researchers have focused more on force injection than force piston operation, leakage after injection or back spray than air and water leakage, and reduction the friction of the plunger without considering the fitting position of the plunger in the barrel.

Model optimization and performance evaluation of hand cranked music box base structure manufactured via 3D printing.

A sound produced from the music box could mesmerize music lovers. The complex mechanism that combined manual with semi-automatics movement creates the music box as a challenge for the manufacturer to innovate and optimize. This study focused on redesigning a hand-cranked music box's base structure using 3D printing and comparing the sound produced with the original model. It is shown that 3D printing can create a complex model with minimum material waste and good repeatability. After remodeling the music box's in a 3D CAD model, the prototype was built, and the tune played by each model was recorded and compared. The results showed that four improvements were made in the barrel mounting, crankshaft holder, crankshaft locker, and comb locker from the built four models. The sound analysis shows that the quality of sound can be improved by using the system's spacer. Furthermore, the finite element method and exact experiment results show that the loudest and best sound quality can be achieved using a 60° angle slope for the music box base structure.

Load-displacement experimental data from axial tensile loading of CFRP-SPCC hybrid laminates.

The current paper shows a data set of load-displacement output from axial tensile loading of CFRP-SPCC hybrid laminates. The specimen geometries are cut based on standard procedure from ASTM D-3039. At least 3 positions in each specimen, we measured its width and thickness. Data of the load and displacement were repeated at least 3 samples in each combination of hybrid laminates. Tensile test was conducted with a 1 mm/min of loading rate. The data were recorded from unloading until failure of specimens. The data gives information about the highest load and the behavior of load-displacement in axial tensile loading. By using width and thickness, normalized data can be obtained, the load can be calculated into stress (MPa) unit. The data are useful for researchers and structural engineers that deals with CFRP, SPCC, and hybrid CFRP-SPCC laminates.

Dataset of material measurement based on SEM images of Ag/TiO2 nanocomposite material synthesized via Horizontal Vapor Phase Growth (HVPG) technique.

This data describes about the measurement technique of Ag/TiO2 nanocomposite materials that successfully synthesized via Horizontal Vapor Phase Growth (HVPG) technique. The data are obtained after specimens were placed in the Scanning Electron Microscope (SEM) chamber to be analyzed. The present data were captured from SEM with different magnification. There are total 27 variable data to be analyzed from three different parameters; growth temperature, baking time and zones. In total, 9 different quartz tubes that contains of Ag/TiO2 nanocomposite material are evaluated. Data are described in average value where the different calculations are presented. Raw data are also embedded in the Appendix for further analysis purposes. These data can be useful as the information of size measurement of Ag/TiO2 nanocomposite materials in different temperature and time during synthesis process.

A standard method to synthesize Ag, Ag/Ge, Ag/TiO2, SnO2, and Ag/SnO2 nanomaterials using the HVPG technique.

Nanotechnology is growing rapidly in the past few decades with the applications in several fields such as medicine, environment, energy, electronics, automotive, and aerospace. There are many methods used by researchers to synthesize nanomaterial. In this paper, Horizontal Vapor Phase Growth (HVPG) technique was successfully used to synthesize various nanomaterial and nanocomposite materials such as Ag, Ag/Ge, Ag/TiO2, SnO2, and Ag/SnO2. HVPG technique used a one-pot step to synthesize nanomaterials with 100 % purity of the results, affordable cost, and environmentally friendly. The method has two variables; growth temperature and curing time. Changing the variables create different shapes of nanomaterials. It also reported that the technique could be used to synthesize various nanomaterials consists of single or multi-material. This detailed method demonstrates the capability of the HVPG technique to synthesize nanomaterials, not only to grow the single shape of nanomaterials but also allow other nanomaterial shapes to grow in different parameter conditions. •HVPG technique successfully used to synthesize various nanomaterials.•Only 2 parameters used; curing time and growth temperature.•Purity result (100 %) with no pollutant.

Structures, mechanical properties and antibacterial activity of Ag/TiO2 nanocomposite materials synthesized via HVPG technique for coating application.

In this study, the structures and mechanical properties of the silver-titanium dioxide nanocomposite material were investigated using Atomic Force Microscopy (AFM). These properties include surface roughness, hardness, and reduced Young's modulus. The nanocomposite material was successfully synthesized using the Horizontal Vapor Phase Growth (HVPG) technique which yielded shapes such as nanoparticles, nanospheres, nanorods, triangular nanocomposites, and nanocrystals. Characterization of nanocomposite materials was done through Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) spectroscopy to elucidate material shape, diameter, and composition. The pour plate technique combined with McFarland standards was used to evaluate the antibacterial activity of the nanocomposite material against Staphylococcus aureus. The nanocomposite material was able to eradicate bacteria and was suitable for coating applications effectively.